Recently I went to a urologist and he measured my testicle size via ultrasound and I was a bit under 15cc and he said that the size is normal but I read that 15cc is not really normal. Should I be worried because of this?

Average testicle volume is usually quoted as about 20 mL (20 cc), with a range of 15-25 being normal. However, it's very difficult to measure testicle size and the authorities differ wildly. In this paper using Japanese men, they got a mean of 36.8 mL measuring with an orchidometer, and 26.3 mL with the same guys, measuring by ultrasound. However, this other paper, using Dutch 18-year-old twins and their siblings, got a mean, by orchidometry, of 15.32 mL for one group and 17.96 mL for the other, with standard deviations of 6.68 mL and 4.48 mL respectively (which is a very big variability).

ultrasound is definitely more accurate. i had an ultrasound but i think that not even reaching 15cc is small. I also read that this can indicate infertility. But I don't want to do a test because I'd be scared of the results.